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Acta Cryst. (2009). E65, o336-o337    [ doi:10.1107/S1600536809001548 ]

3-(2,4-Dichlorophenyl)-1,5-di-2-furylpentane-1,5-dione

H.-K. Fun, R. Kia, P. S. Patil and S. M. Dharmaprakash

Abstract top

In the title compound, C19H14Cl2O4, intramolecular C-H...O and C-H...Cl hydrogen bonds generate S(6) and S(5) ring motifs, respectively. In the crystal structure, intermolecular C-H...O interactions between symmetry-related molecules involving two methylene groups and an O atom as a bifurcated acceptor generate an R21(6) ring motif. In the molecule, one of the furan rings is rotationally disordered by approximately 180° about the single C-C bond to which it is attached; the refined site-occupancy factors are 0.505 (7) and 0.495 (7). The major component of the disordered furan ring and the benzene ring form a dihedral angle of 88.8 (4)°. The dihedral angle between the major disorder component and the other furan ring is 81.9 (4)°. In addition, the crystal structure is stabilized by further intermolecular C-H...O (×2) hydrogen bonds and C-H...[pi] interactions.

Comment top

Over the past several decades, linear π-conjugated organic molecules have attracted considerable interest because of their promising applications (such as for organic light-emitting diodes, non-linear optical properties, conductivity and photocells) due to their delocalized π systems (Li et al., 2004; Patil, Teh et al., 2007; Patil, Fun et al., 2007). In the course of our synthesis of the π-conjugated organic molecule, the title compound, (Fig. 1) was synthesized and its crystal structure is reported here.

In the title molecular structure (Fig.1), one of the furane rings has an approximately 180° rotational disorder (atoms of the minor part are lablled with the suffix X) about the C9—C10 single bond. The bond lengths (Allen et al., 1987) and angles are within the normal values. The ratio of the refined site-occupancy factors of the major and minor parts of the disordered furane ring is 0.505 (7)/0.495 (7). The major part of the disordered furane ring and the benzene ring are twisted from each other by the dihedral angle of 88.8 (4)°. Intramolecular C—H···O and C—H···Cl hydrogen bonds (Table 1), generate S(6) and S(5) ring motifs, respectively. Intermolecular C—H···O interactions (Table 1) between the neighbouring molecules involving two methylene groups and an oxygen atom as a bifurcated acceptor generate R21(6) ring motif. In the crystal packing (Fig. 2), intermolecular C—H···O interactions link neighbouring molcules into a chain along the c axis.

Related literature top

For details of hydrogen-bond motifs, see: Bernstein et al. (1995). For related structures and physico-chemical properties, see, for example: Li et al. (2004); Patil, Teh et al. (2007); Patil, Fun et al. (2007). For bond-length data, see: Allen et al. (1987). Cg1 is the centroid of the C14–C19 benzene ring.

Experimental top

The title compound was synthesized by the condensation of 2,4-Dichlorobenzaldehyde (0.01 mol, 1.75 mg) with 2-acetylfuran (0.02 mol, 2.02 ml) in methanol (80 ml) in the presence of a catalytic amount of sodium hydroxide solution (5 ml, 30%). After stirring (6 h), the contents of the flask were poured into ice-cold water (500 ml) and left to stand for 5 h. The resulting crude solid was filtered and dried. Crystals suitable for X-ray analysis were grown by slow evaporation of an acetone solution at room temperature.

Refinement top

All hydrogen atoms were postioned geometrically in the riding model approximation with C—H= 0.93 Å, and Uiso (H) = 1.2Ueq (C). Initially rigid, similarity and simulation restraints were applied to the disordered furane ring. After steady state has been reached, these restraints were removed for the final refinement. No restraint was used in the final refinement.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atomic numbering. Open bonds indicate the minor disordered component. Dashed lines show intramolecular hydrogen bonds.
[Figure 2] Fig. 2. The crystal packing of the major component of (I), viewed down the b-axis, showing a chain of molecules along the c-axis. Intramolecular and intermolecular interactions are drawn as dashed lines.
3-(2,4-Dichlorophenyl)-1,5-di-2-furylpentane-1,5-dione top
Crystal data top
C19H14Cl2O4F(000) = 776
Mr = 377.20Dx = 1.477 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 6655 reflections
a = 9.9116 (1) Åθ = 2.4–33.5°
b = 17.7480 (3) ŵ = 0.40 mm−1
c = 10.1173 (2) ÅT = 100 K
β = 107.612 (1)°Block, colourless
V = 1696.32 (5) Å30.22 × 0.14 × 0.05 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer		6622 independent reflections
Radiation source: fine-focus sealed tube5037 reflections with I > 2˘I)
graphiteRint = 0.042
φ and ω scansθmax = 33.6°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		h = −15→15
Tmin = 0.918, Tmax = 0.981k = −27→27
29237 measured reflectionsl = −15→14
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.113H-atom parameters constrained
S = 1.10 w = 1/[σ2(Fo2) + (0.0518P)2 + 0.2913P]
where P = (Fo2 + 2Fc2)/3
6622 reflections(Δ/σ)max = 0.001
263 parametersΔρmax = 0.47 e Å−3
0 restraintsΔρmin = −0.36 e Å−3
Crystal data top
C19H14Cl2O4V = 1696.32 (5) Å3
Mr = 377.20Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.9116 (1) ŵ = 0.40 mm−1
b = 17.7480 (3) ÅT = 100 K
c = 10.1173 (2) Å0.22 × 0.14 × 0.05 mm
β = 107.612 (1)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer		6622 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		5037 reflections with I > 2˘I)
Tmin = 0.918, Tmax = 0.981Rint = 0.042
29237 measured reflectionsθmax = 33.6°
Refinement top
R[F2 > 2σ(F2)] = 0.041H-atom parameters constrained
wR(F2) = 0.113Δρmax = 0.47 e Å−3
S = 1.10Δρmin = −0.36 e Å−3
6622 reflectionsAbsolute structure: ?
263 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Experimental. The low-temperature data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Cl10.38051 (3)0.605962 (19)0.52165 (3)0.02599 (8)
Cl2−0.09927 (3)0.69351 (2)0.14183 (4)0.03110 (9)
O10.67813 (10)0.93790 (6)0.42430 (11)0.0302 (2)
O20.53954 (9)0.80850 (5)0.46030 (9)0.02198 (18)
O30.81229 (10)0.60583 (6)0.43590 (11)0.0304 (2)
C10.75581 (16)0.98987 (8)0.3790 (2)0.0407 (4)
H1A0.77741.03780.41640.049*
C20.79639 (17)0.96291 (9)0.2745 (2)0.0405 (4)
H2A0.85000.98790.22710.049*
C30.74192 (14)0.88814 (8)0.24929 (15)0.0254 (3)
H3A0.75250.85480.18220.031*
C40.67168 (12)0.87570 (7)0.34297 (13)0.0194 (2)
C50.60146 (11)0.80821 (6)0.37231 (12)0.0168 (2)
C60.61549 (12)0.73848 (6)0.29237 (13)0.0179 (2)
H6A0.71510.72680.31080.021*
H6B0.57630.74860.19390.021*
C70.54043 (12)0.66983 (6)0.32935 (13)0.0171 (2)
H7A0.57210.66470.43050.021*
C80.58102 (12)0.59720 (6)0.26816 (13)0.0198 (2)
H8A0.51560.55760.27390.024*
H8B0.57080.60540.17080.024*
C90.73035 (13)0.57107 (7)0.34030 (13)0.0214 (2)
C100.77185 (14)0.49951 (7)0.29298 (14)0.0242 (3)
O40.8896 (11)0.4658 (4)0.3532 (8)0.0238 (17)0.505 (7)
C110.8971 (13)0.3977 (7)0.3023 (9)0.0210 (13)0.505 (7)
H11A0.97370.36520.33410.025*0.505 (7)
C120.7754 (9)0.3813 (4)0.1953 (9)0.0206 (10)0.505 (7)
H12A0.75510.33760.14230.025*0.505 (7)
C130.6897 (8)0.4453 (3)0.1847 (8)0.0176 (9)0.505 (7)
H13A0.59980.45270.12280.021*0.505 (7)
O4X0.6852 (6)0.4628 (3)0.2027 (6)0.0189 (8)0.495 (7)
C11X0.7518 (9)0.3984 (4)0.1882 (10)0.0251 (13)0.495 (7)
H11B0.70880.36030.12690.030*0.495 (7)
C12X0.8834 (13)0.3948 (7)0.2692 (10)0.0250 (17)0.495 (7)
H12B0.94820.35630.27350.030*0.495 (7)
C13X0.9064 (19)0.4644 (7)0.3512 (14)0.0261 (17)0.495 (7)
H13B0.98560.48090.42100.031*0.495 (7)
C140.38037 (12)0.67715 (6)0.28323 (12)0.0166 (2)
C150.30627 (12)0.70752 (7)0.15451 (13)0.0192 (2)
H15A0.35690.72520.09700.023*
C160.15938 (12)0.71228 (7)0.10920 (13)0.0211 (2)
H16A0.11250.73280.02290.025*
C170.08406 (12)0.68587 (7)0.19492 (14)0.0209 (2)
C180.15200 (12)0.65386 (7)0.32252 (13)0.0199 (2)
H18A0.10080.63580.37920.024*
C190.29875 (12)0.64942 (6)0.36363 (12)0.0175 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.02556 (15)0.03169 (16)0.02196 (16)−0.00052 (11)0.00903 (12)0.00834 (11)
Cl20.01501 (13)0.0454 (2)0.03221 (19)−0.00001 (12)0.00608 (12)−0.00328 (14)
O10.0295 (5)0.0250 (5)0.0360 (6)−0.0014 (4)0.0100 (4)−0.0086 (4)
O20.0226 (4)0.0261 (4)0.0190 (4)0.0000 (3)0.0089 (3)−0.0021 (3)
O30.0255 (5)0.0352 (5)0.0257 (5)0.0090 (4)0.0007 (4)0.0001 (4)
C10.0310 (7)0.0182 (6)0.0712 (12)−0.0024 (5)0.0129 (7)−0.0048 (7)
C20.0357 (8)0.0300 (7)0.0614 (11)0.0016 (6)0.0229 (8)0.0172 (7)
C30.0285 (6)0.0256 (6)0.0246 (6)0.0034 (5)0.0116 (5)0.0034 (5)
C40.0194 (5)0.0191 (5)0.0177 (5)0.0004 (4)0.0029 (4)−0.0009 (4)
C50.0140 (4)0.0203 (5)0.0146 (5)0.0006 (4)0.0021 (4)−0.0007 (4)
C60.0168 (5)0.0198 (5)0.0184 (5)−0.0010 (4)0.0073 (4)−0.0017 (4)
C70.0160 (5)0.0175 (5)0.0186 (5)0.0007 (4)0.0063 (4)0.0010 (4)
C80.0174 (5)0.0183 (5)0.0242 (6)0.0018 (4)0.0068 (4)0.0006 (4)
C90.0216 (5)0.0226 (5)0.0218 (6)0.0047 (4)0.0094 (4)0.0058 (4)
C100.0263 (6)0.0244 (6)0.0261 (6)0.0093 (5)0.0144 (5)0.0089 (5)
O40.020 (3)0.0189 (18)0.027 (2)−0.0004 (16)−0.0008 (16)−0.0070 (17)
C110.0140 (17)0.025 (2)0.023 (3)−0.0002 (14)0.003 (2)−0.003 (2)
C120.028 (2)0.013 (2)0.0247 (17)0.0017 (17)0.0136 (17)−0.0035 (18)
C130.0187 (15)0.014 (2)0.0185 (19)−0.0006 (19)0.0035 (12)−0.0019 (15)
O4X0.0193 (10)0.014 (2)0.0229 (18)0.0024 (14)0.0063 (11)−0.0018 (12)
C11X0.029 (3)0.019 (3)0.031 (2)−0.003 (2)0.014 (2)−0.007 (2)
C12X0.024 (3)0.0161 (15)0.036 (5)0.0023 (18)0.010 (3)−0.008 (3)
C13X0.016 (2)0.024 (3)0.035 (3)0.0092 (16)0.0019 (18)0.012 (3)
C140.0165 (5)0.0154 (5)0.0192 (5)−0.0006 (4)0.0074 (4)−0.0011 (4)
C150.0191 (5)0.0205 (5)0.0194 (6)0.0003 (4)0.0080 (4)0.0010 (4)
C160.0189 (5)0.0235 (5)0.0203 (6)0.0012 (4)0.0051 (4)0.0001 (4)
C170.0145 (5)0.0230 (5)0.0254 (6)−0.0010 (4)0.0062 (4)−0.0055 (4)
C180.0194 (5)0.0210 (5)0.0222 (6)−0.0033 (4)0.0105 (4)−0.0032 (4)
C190.0191 (5)0.0168 (5)0.0172 (5)−0.0005 (4)0.0065 (4)−0.0004 (4)
Geometric parameters (Å, °) top
Cl1—C191.7388 (12)C10—O41.289 (10)
Cl2—C171.7373 (12)C10—C13X1.427 (16)
O1—C11.3663 (19)C10—C131.499 (7)
O1—C41.3668 (15)O4—C111.324 (14)
O2—C51.2247 (14)C11—C121.386 (13)
O3—C91.2249 (16)C11—H11A0.9300
C1—C21.329 (3)C12—C131.403 (9)
C1—H1A0.9300C12—H12A0.9300
C2—C31.426 (2)C13—H13A0.9300
C2—H2A0.9300O4X—C11X1.350 (7)
C3—C41.3531 (18)C11X—C12X1.315 (14)
C3—H3A0.9300C11X—H11B0.9300
C4—C51.4603 (16)C12X—C13X1.466 (18)
C5—C61.5077 (16)C12X—H12B0.9300
C6—C71.5318 (16)C13X—H13B0.9300
C6—H6A0.9700C14—C151.3954 (17)
C6—H6B0.9700C14—C191.3988 (16)
C7—C141.5177 (15)C15—C161.3904 (16)
C7—C81.5354 (16)C15—H15A0.9300
C7—H7A0.9800C16—C171.3859 (17)
C8—C91.5116 (16)C16—H16A0.9300
C8—H8A0.9700C17—C181.3845 (18)
C8—H8B0.9700C18—C191.3888 (16)
C9—C101.4596 (18)C18—H18A0.9300
C10—O4X1.234 (5)
C1—O1—C4105.77 (12)O4—C10—C13105.1 (4)
C2—C1—O1111.13 (13)C13X—C10—C13104.7 (6)
C2—C1—H1A124.4C9—C10—C13130.8 (3)
O1—C1—H1A124.4C10—O4—C11112.9 (8)
C1—C2—C3106.75 (13)O4—C11—C12110.9 (10)
C1—C2—H2A126.6O4—C11—H11A124.5
C3—C2—H2A126.6C12—C11—H11A124.5
C4—C3—C2105.87 (13)C11—C12—C13104.7 (8)
C4—C3—H3A127.1C11—C12—H12A127.7
C2—C3—H3A127.1C13—C12—H12A127.7
C3—C4—O1110.47 (11)C12—C13—C10106.3 (6)
C3—C4—C5130.85 (12)C12—C13—H13A126.8
O1—C4—C5118.59 (11)C10—C13—H13A126.8
O2—C5—C4121.26 (11)C10—O4X—C11X105.8 (6)
O2—C5—C6122.77 (10)C12X—C11X—O4X113.5 (8)
C4—C5—C6115.93 (10)C12X—C11X—H11B123.2
C5—C6—C7113.04 (9)O4X—C11X—H11B123.2
C5—C6—H6A109.0C11X—C12X—C13X105.4 (11)
C7—C6—H6A109.0C11X—C12X—H12B127.3
C5—C6—H6B109.0C13X—C12X—H12B127.3
C7—C6—H6B109.0C10—C13X—C12X99.7 (10)
H6A—C6—H6B107.8C10—C13X—H13B130.1
C14—C7—C6113.36 (9)C12X—C13X—H13B130.1
C14—C7—C8108.96 (9)C15—C14—C19116.42 (10)
C6—C7—C8111.30 (9)C15—C14—C7121.74 (10)
C14—C7—H7A107.7C19—C14—C7121.72 (10)
C6—C7—H7A107.7C16—C15—C14122.28 (11)
C8—C7—H7A107.7C16—C15—H15A118.9
C9—C8—C7113.62 (10)C14—C15—H15A118.9
C9—C8—H8A108.8C17—C16—C15118.80 (12)
C7—C8—H8A108.8C17—C16—H16A120.6
C9—C8—H8B108.8C15—C16—H16A120.6
C7—C8—H8B108.8C18—C17—C16121.34 (11)
H8A—C8—H8B107.7C18—C17—Cl2119.24 (9)
O3—C9—C10120.79 (11)C16—C17—Cl2119.42 (10)
O3—C9—C8123.03 (11)C17—C18—C19118.19 (11)
C10—C9—C8116.14 (11)C17—C18—H18A120.9
O4X—C10—O4115.7 (4)C19—C18—H18A120.9
O4X—C10—C13X115.4 (6)C18—C19—C14122.92 (11)
O4X—C10—C9120.0 (3)C18—C19—Cl1117.07 (9)
O4—C10—C9123.6 (4)C14—C19—Cl1120.01 (9)
C13X—C10—C9124.4 (6)
C4—O1—C1—C20.25 (18)C11—C12—C13—C100.3 (9)
O1—C1—C2—C3−0.04 (19)O4X—C10—C13—C12−166 (3)
C1—C2—C3—C4−0.19 (17)O4—C10—C13—C120.1 (7)
C2—C3—C4—O10.35 (15)C13X—C10—C13—C124.8 (9)
C2—C3—C4—C5−175.99 (13)C9—C10—C13—C12−172.2 (4)
C1—O1—C4—C3−0.37 (15)O4—C10—O4X—C11X−5.6 (8)
C1—O1—C4—C5176.48 (12)C13X—C10—O4X—C11X−0.6 (9)
C3—C4—C5—O2−178.14 (13)C9—C10—O4X—C11X−176.2 (4)
O1—C4—C5—O25.76 (17)C13—C10—O4X—C11X9(3)
C3—C4—C5—C64.29 (19)C10—O4X—C11X—C12X−1.0 (10)
O1—C4—C5—C6−171.80 (10)O4X—C11X—C12X—C13X2.0 (14)
O2—C5—C6—C71.96 (16)O4X—C10—C13X—C12X1.6 (12)
C4—C5—C6—C7179.49 (10)O4—C10—C13X—C12X96 (12)
C5—C6—C7—C1467.88 (13)C9—C10—C13X—C12X177.1 (6)
C5—C6—C7—C8−168.86 (10)C13—C10—C13X—C12X−0.2 (11)
C14—C7—C8—C9−162.04 (10)C11X—C12X—C13X—C10−2.0 (13)
C6—C7—C8—C972.23 (13)C6—C7—C14—C1541.31 (15)
C7—C8—C9—O3−1.98 (17)C8—C7—C14—C15−83.23 (13)
C7—C8—C9—C10175.93 (10)C6—C7—C14—C19−142.87 (11)
O3—C9—C10—O4X175.4 (3)C8—C7—C14—C1992.60 (13)
C8—C9—C10—O4X−2.6 (4)C19—C14—C15—C161.82 (17)
O3—C9—C10—O45.5 (6)C7—C14—C15—C16177.86 (11)
C8—C9—C10—O4−172.5 (6)C14—C15—C16—C17−0.04 (18)
O3—C9—C10—C13X0.1 (8)C15—C16—C17—C18−1.23 (18)
C8—C9—C10—C13X−177.8 (7)C15—C16—C17—Cl2178.40 (9)
O3—C9—C10—C13176.6 (4)C16—C17—C18—C190.61 (18)
C8—C9—C10—C13−1.4 (5)Cl2—C17—C18—C19−179.03 (9)
O4X—C10—O4—C112.2 (11)C17—C18—C19—C141.33 (17)
C13X—C10—O4—C11−86 (12)C17—C18—C19—Cl1−177.82 (9)
C9—C10—O4—C11172.5 (7)C15—C14—C19—C18−2.49 (17)
C13—C10—O4—C11−0.6 (10)C7—C14—C19—C18−178.53 (11)
C10—O4—C11—C120.8 (14)C15—C14—C19—Cl1176.63 (9)
O4—C11—C12—C13−0.7 (12)C7—C14—C19—Cl10.59 (15)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C6—H6A···O30.972.533.1213 (16)119
C6—H6B···O2i0.972.493.3194 (15)143
C7—H7A···Cl10.982.573.0739 (12)112
C8—H8B···O2i0.972.563.4492 (15)152
C1—H1A···Cg1ii0.932.973.6095 (16)127
Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) −x+1, y+1/2, −z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C6—H6A···O30.972.533.1213 (16)119
C6—H6B···O2i0.972.493.3194 (15)143
C7—H7A···Cl10.982.573.0739 (12)112
C8—H8B···O2i0.972.563.4492 (15)152
C1—H1A···Cg1ii0.932.973.6095 (16)127
Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) −x+1, y+1/2, −z+1/2.
Acknowledgements top

This work was supported by the Department of Science and Technology (DST), Government of India (grant No. SR/S2/LOP-17/2006). HKF and RK thank the Malaysian Government and Universiti Sains Malaysia for the Science Fund grant (No. 305/PFIZIK/613312). RK thanks Universiti Sains Malaysia for a post-doctoral research fellowship. HKF also thanks Universiti Sains Malaysia for the Research University Golden Goose grant (No. 1001/PFIZIK/ 811012).

references
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